Migrate SafePack to Viem (#53)

We no longer require ethers in the lib/utils directory. This is a move toward a bit more type safety, consistency and detanglement from the network client and the contract instances.

Last step to remove ethers entirely will be to replace the ethers.JsonRpcProvider with PublicClient in lib/bundler. Then we can move ethers to a dev dependency and use it for unit testing our encodings.

examples/send-tx.ts

@@ -1,5 +1,6 @@
 import dotenv from "dotenv";
 import { ethers } from "ethers";
+import { isAddress } from "viem";
 
 import { loadArgs, loadEnv } from "./cli";
 import { TransactionManager } from "../src";
@@ -29,7 +30,11 @@ async function main(): Promise<void> {
     },
   ];
   // Add Recovery if safe not deployed & recoveryAddress was provided.
-  if (!(await txManager.safeDeployed(chainId)) && recoveryAddress) {
+  if (
+    !(await txManager.safeDeployed(chainId)) &&
+    recoveryAddress &&
+    isAddress(recoveryAddress)
+  ) {
     const recoveryTx = txManager.addOwnerTx(recoveryAddress);
     // This would happen (sequentially) after the userTx, but all executed in a single
     transactions.push(recoveryTx);

src/lib/bundler.ts

@@ -25,7 +25,9 @@ export class Erc4337Bundler {
     this.entryPointAddress = entryPointAddress;
     this.apiKey = apiKey;
     this.chainId = chainId;
-    this.provider = new ethers.JsonRpcProvider(bundlerUrl(chainId, this.apiKey));
+    this.provider = new ethers.JsonRpcProvider(
+      bundlerUrl(chainId, this.apiKey)
+    );
   }
 
   async getPaymasterData(